Osteogenic Exercise Research Articles

Effects of non-supervised exercise interventions on bone mineral density in adult women: a systematic review and meta‑analysis.

Mini abstractOsteoporosis is a major health issue worldwide. This study analyzes the effects of non-supervised osteoporosis prevention programs on bone mineral density. Non-supervised exercise increases femoral neck and lumbar spine bone mineral density in adult women. Thus, it might be effective for preventing or treating osteoporosis or osteopenia in this population.IntroductionOsteoporosis is a major health issue worldwide. Social distancing measures due to COVID-19 have hindered the chances to take part in supervised osteoporosis prevention exercise programs. The purpose of the present study is to systematically review and meta-analyze the effects of non-supervised osteoporosis prevention exercise programs on bone mineral density (BMD) in adult women.MethodsA comprehensive search of electronic databases (n = 7) was conducted including (a) prospective randomized controlled trials (RCTs) comparing at least one exercise group vs. a control group with sedentary lifestyle or sham exercises; (b) baseline and follow-up BMD values, or BMD changes from baseline, at any skeletal site; (c) women over 30 years old; and (d) non-supervised exercise programs only. Subgroup analyses were performed for menopausal status, intervention duration, type of exercise, and osteopenia/osteoporosis status.ResultsTen studies were included (n = 668). Random effect analyses showed that unsupervised exercise had beneficial effects on lumbar spine (LS) BMD with standardized mean difference (SMD) = 0.40 (95% confidence interval (CI): 0.03–0.77), and femoral neck (FN) BMD with SMD = 0.51 (95% CI: 0.16–0.85). Unsupervised exercise increased LS (SMD = 0.73 (95% CI: 0.13–1.33)) and FN BMD (SMD = 0.85 (95% CI: 0.33–1.37)) in women with osteopenia/osteoporosis, but not in healthy counterparts.ConclusionNon-supervised exercise improves FN and LS BMD in adult women. Beneficial effects of exercise on FN and LS BMD might be more pronounced in those with poor bone health compared with healthy counterparts. More RCTs prescribing non-supervised, osteogenic exercise are required in this population. It is necessary to investigate the efficacy of remote/assistive technologies for delivering and monitoring non-supervised exercise interventions.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00198-022-06357-3.

The Quantification, Autoregulation and Reliability of the Stomp as an Osteogenic Exercise

The Quantification, Autoregulation and Reliability of the Stomp as an Osteogenic Exercise

Does Physical Exercise Always Improve Bone Quality in Rats?

For decades, the osteogenic effect from different physical activities on bone in rodents remained uncertain. This literature review presents for the first time the effects on five exercise models (treadmill running, wheel running, swimming, resistance training and vibration modes) in three different experimental rat groups (males, females, osteopenic) on bone quality. The bone parameters presented are bone mineral density, micro-architectural and mechanical properties, and osteoblast/osteocyte and osteoclast parameters. This review shows that physical activities have a positive effect (65% of the results) on bone status, but we clearly observed a difference amongst the different protocols. Even if treadmill running is the most used protocol, the resistance training constitutes the first exercise model in term of osteogenic effects (87% of the whole results obtained on this model). The less osteogenic model is the vibration mode procedure (31%). It clearly appears that the gender plays a role on the bone response to swimming and wheel running exercises. Besides, we did not observe negative results in the osteopenic population with impact training, wheel running and vibration activities. Moreover, about osteoblast/osteocyte parameters, we conclude that high impact and resistance exercise (such jumps and tower climbing) seems to increase bone formation more than running or aerobic exercise. Among the different protocols, literature has shown that the treadmill running procedure mainly induces osteogenic effects on the viability of the osteocyte lineage in both males and females or ovariectomized rats; running in voluntary wheels contributes to a negative effect on bone metabolism in older male models; whole-body vertical vibration is not an osteogenic exercise in female and ovariectomized rats; whereas swimming provides controversial results in female models. For osteoclast parameters only, running in a voluntary wheel for old males, the treadmill running program at high intensity in ovariectomized rats, and the swimming program in a specific ovariectomy condition have detrimental consequences.

Functional electrical stimulation (FES)-assisted rowing combined with zoledronic acid, but not alone, preserves distal femur strength and stiffness in people with chronic spinal cord injury.

People with spinal cord injury (SCI) have high fracture risk at the knee after the injury. Therapies that prevent bone loss or stimulate an anabolic response in bone have been proposed to reduce fractures. Zoledronic acid (ZA) is a potent bisphosphonate that inhibits osteoclastic resorption. Functional electrical stimulation (FES)-assisted rowing is a potentially osteogenic exercise involving mechanical stimulation to the lower extremities. Here, we investigated the effect of FES-assisted rowing with and without ZA on bone strength and stiffness in individuals with SCI. Twenty individuals from a cohort of adults with SCI who participated in a clinical trial were included in the study. CT scans of their knees before and after the intervention were converted to finite element models. Bone failure strength (Tult) and stiffness were calculated at the proximal tibia and distal femur. Tult at the distal femur increased 4.6% among people who received rowing + ZA and decreased 13.9% among those with rowing only (p < 0.05 for group). Torsional and compressive stiffness at the femur metaphysis increased in people with rowing + ZA (+ 3 to +4%) and decreased in people with rowing only (- 7 to -8%; p < 0.05). Tult in the proximal tibia decreased in everyone, but the loss was attenuated in the rowing + ZA group. People with initially stronger bone tended to lose more strength. Overall, we observed increases in bone strength at the distal femur but not the proximal tibia, with FES-assisted rowing combined with ZA treatment. Rowing alone did not significantly prevent bone loss at either site, which might be attributed to insufficient mechanical loading.

Enjoyability And Acceptability Of Bone Targeted Exercise For Young Adult Women: The OPTIMA-Ex Trial

PURPOSE: While physical activity participation is recognized as an effective modifiable risk factor for osteoporosis, adherence and compliance present significant challenges. We aimed to explore the experiences related to a bone-targeted exercise intervention, determine enjoyment and acceptability of each exercise mode, and identify barriers and facilitators to osteogenic exercise for young adult women with low bone mass. METHODS: A mixed-methods study was conducted within the OPTIMA-Ex trial, a three-arm RCT comparing musculoskeletal outcomes from high-intensity impact training (IT), high-intensity resistance training (RT), and a home-based low-intensity exercise control (CON). All 32 participants (IT=10, RT=12, CON=10) who finished the trial completed questionnaires on physical activity enjoyment (PACES-8, Kruskal-Wallis and Friedman’s test), quality of life (AQoL-6D, repeated measures ANOVA), and semi-structured interviews to facilitate qualitative analysis (Leximancer v4.50) of participant experiences. RESULTS: At follow-up, RT had the highest total score for PACES-8 (48.6±4.7), while only the IT group experienced an increase in total score over the 10 months (34.8±4.1 to 41.4±6.9, p<0.05). Only CON experienced an improvement in total AQoL-6D score. For the sub-domains, all groups experienced clinically significant improvements (>0.06 points) for ‘mental health’, while IT improved for ‘senses’ and CON improved for ‘coping’ (p<0.05). The qualitative analysis revealed that overall trial exercises were viewed positively by all groups, yet the two high-intensity groups had the ‘richest’ exercise experiences, developing a more positive attitude to exercise. Barriers to exercise related to time, convenience, accessibility, and cost. Both IT and CON groups experienced a 41% drop out compared to 29% in the RT group. Compliance did not differ between CON (78.8±4.1%), IT (61.4±15.1%), or RT (66.4±11.2%) (p=0.085). CONCLUSIONS: While IT and RT provide enjoyable bone-targeted exercise experiences for young adult women, on balance RT appears most favorable. It seems prudent, that bone-targeted exercise interventions for this demographic address perceptions of time demands and environmental barriers to participation in order to maximize compliance and adherence.

Enjoyment and acceptability of different exercise modalities to improve bone health in young adult women.

Osteoporosis presents a serious public health issue and physical activity is recognised as the most effective modifiable risk factor for the condition. The reasons behind physical activity participation, however, are complex. We therefore aimed to explore the experiences related to a bone-targeted exercise intervention, determine enjoyment and acceptability of each exercise mode, and identify barriers and facilitators to osteogenic exercise for young adult women. The present study was conducted within the Osteoporosis Prevention Through Impact and Muscle-loading Approaches to Exercise (OPTIMA-Ex) trial, a three-arm RCT comparing musculoskeletal outcomes from two supervised, high-intensity, exercise programs (impact and resistance training) with an unsupervised low-intensity exercise control. A mixed-methods approach was used, including quality of life and physical activity enjoyment questionnaires and qualitative analysis of semi-structured interviews. All groups had improvements in the 'mental health' domain of the quality of life measure; however, the two supervised exercise groups had greater levels of physical activity enjoyment. The qualitative analysis revealed that overall the trial activities were positively, yet the two supervised groups had 'richer' exercise experiences. Motivations for participation, barriers to physical activity and desired continuation of participation differed between all three groups. Findings suggest that bone-targeted exercise interventions for young adult women must address perceived time demands and environmental barriers to participation in order to maximise compliance and adherence. SO WHAT?: As physical activity is the most effective lifestyle strategy to improve bone health and young adulthood an important window for its augmentation, increasing convenience, accessibility and understanding of osteoporosis preventative behaviours in this demographic is vital.

Bone gain following loading is site-specifically enhanced by prior and concurrent disuse in aged male mice.

The primary aim of osteoanabolic therapies is to strategically increase bone mass in skeletal regions likely to experience high strains. In the young healthy skeleton, this is primarily achieved by bone's adaptation to loading. This adaptation appears to fail with age, resulting in osteoporosis and fractures. We previously demonstrated that prior and concurrent disuse enhances bone gain following loading in old female mice. Here, we applied site specificity micro-computed tomography analysis to map regional differences in bone anabolic responses to axial loading of the tibia between young (19-week-old) and aged (19-month-old), male and female mice. Loading increased bone mass specifically in the proximal tibia in both sexes and ages. Young female mice gained more cortical bone than young males in specific regions of the tibia. However, these site-specific sex differences were lost with age such that bone gain following loading was not significantly different between old males and females. To test whether disuse enhances functional adaption in old male mice as it does in females, old males were subjected to sciatic neurectomy or sham surgery, and loading was initiated four days after surgery. Disuse augmented tibial cortical bone gain in response to loading in old males, but only in regions which were load-responsive in the young. Prior and concurrent disuse also increased loading-induced trabecular thickening in the proximal tibia of old males. Understanding how diminished background loading rejuvenates the osteogenic loading response in the old may improve osteogenic exercise regimes and lead to novel osteoanabolic therapies.

Bilateral multidirectional jumps with reactive jump-landings achieve osteogenic thresholds with and without instruction in premenopausal women

BackgroundCurrently jump-landing ground reaction forces have only been quantified in the vertical direction as a stimulus for bone development. This study quantified the full-spectrum of jump-landing force magnitudes (body weight's) and rates of strain (body weights per second) of bilateral multidirectional jumps (star jump and stride jump) with reactive jump-landings (i.e. jumping immediately after initial jump-landing) among premenopausal women. It was also of interest to quantify the influence of instruction on the magnitude and rate of the jump-landing ground reaction forces. MethodsTwenty-one women [Mean (SD): 43.3(5.9)yr; 69.4(9.6)kg; 167(5.5)cm; 27.5(8.7)% body fat] performed a jump testing session ‘with instruction’ followed by a jump testing session performed one week later with ‘instruction withdrawn’. FindingsThe resultant magnitudes (3.90 to 5.38, body weights) and rates of strain (192 to 329, body weights per second) for the jump-landings, performed on a force plate, exceeded previously determined osteogenic thresholds (>3body weight's and >43body weights per second, respectively). An instruction effect was observed for resultant (↑8% and ↑12%; P ≤ .01) and vertical (↑8% and ↑7%; P ≤ .01) ground reaction force's (Newtons and body weight, respectively) indicating learning/practice effects for these exercises. A jump-landing effect was observed, with larger peak rates of strain (↑29%; P < .0001, body weight per second) and peak forces (↑12% to ↑48%; P ≤ .01, body weights) for the second jump-landing (post-reactive jump). InterpretationThese multidirectional bilateral jumps represent a unique training stimulus for premenopausal women and achieve osteogenic thresholds thought pre-requisite for bone growth and could be utilized in the development of osteogenic exercise programs.

Consumption of Greek yogurt during 12 weeks of high-impact loading exercise increases bone formation in young, adult males – a secondary analysis from a randomized trial

Exercise combined with protein and calcium has been shown to benefit bone turnover and bone metabolism. Greek yogurt (GY) contains important nutrients that support bone but has yet to be studied with exercise for this purpose. Thirty untrained, university-aged, males were randomized to 2 groups (n = 15/group): GY (20 g protein, 208 mg calcium/dose) or placebo pudding (PP; 0 g protein, 0 g calcium/dose) consumed 3×/day on training days and 2×/day on nontraining days. Both groups underwent a resistance/plyometric training program for 12 weeks. Blood was obtained at weeks 0, 1, and 12 to measure procollagen-type-I-N-terminal-propeptide (P1NP) and C-terminal-telopeptide (CTX). After outlier treatment, P1NP increased more over time in GY versus PP (p = 0.002; interaction). Both groups decreased CTX over time (p = 0.046; time effect). Following 1 week of training, there was a trend towards a significant increase in CTX in PP with no change in GY (p = 0.062; interaction). P1NP changed more in GY than PP (baseline to week 12; p = 0.029) as did the P1NP/CTX ratio (p = 0.015) indicating a greater increase in formation with GY. Thus, GY added to a high-load, high-impact exercise program positively shifted bone turnover towards increased formation while attenuating resorption. GY could be a plausible postexercise food to support bone health in young adult males. Novelty Greek yogurt, with exercise, increased bone formation in young adult males over 12 weeks. After 1 week of an osteogenic exercise program, Greek yogurt tended to blunt a rise in bone resorption seen with the placebo. Greek yogurt is a plausible postexercise food that supports bone.

Novel insights into the complex architecture of osteoporosis molecular genetics.

Osteoporosis is a prevalent osteodegenerative disease and silent killer linked to a decrease in bone mass and decline of bone microarchitecture, due to impaired bone matrix mineralization, raising the risk of fracture. Nevertheless, the process of bone matrix mineralization is still an unsolved mystery. Osteoporosis is a polygenic disorder associated with genetic and environmental risk factors; however, the majority of genes associated with osteoporosis remain largely unknown. Several signaling pathways regulate bone mass; therefore, dysregulation of a single signaling pathway leads to metabolic bone disease owing to high or low bone mass. Parathyroid hormone, core-binding factor α-1 (Cbfa1), Wnt/β-catenin, the receptor activator of the nuclear factor kappa-B (NF-κB) ligand (RANKL), myostatin, and osteogenic exercise signaling pathways play pivotal roles in the regulation of bone mass. The myostatin signaling pathway increases bone resorption by activating the RANKL signaling pathway, whereas osteogenic exercise inhibits myostatin and sclerostin while inducing irisin that consequentially activates the Cbfa1 and Wnt/β-catenin bone formation pathways. The aims of this review are to summarize what is known about osteoporosis-related signaling pathways; define the role of these pathways in osteoporosis drug discovery; focus light on the link between bone, muscle, pancreas, and adipose integrative physiology and osteoporosis; and underline the emerging role of osteogenic exercise in the prevention of, and care for, osteoporosis, obesity, and diabetes.

Peripheral QCT Sector Analysis Reveals Positive Bone Adaptations Following Osteogenic Index-Optimized Exercise

Peripheral QCT Sector Analysis Reveals Positive Bone Adaptations Following Osteogenic Index-Optimized Exercise

Rest intervals reduce the number of loading bouts required to enhance bone formation.

As our society becomes increasingly sedentary, compliance with exercise regimens that require numerous high-energy activities each week become less likely. Alternatively, given an osteogenic exercise intervention that required minimal effort, it is reasonable to presume that participation would be enhanced. Insertion of brief rest intervals between each cycle of mechanical loading holds potential to achieve this result because substantial osteoblast function is activated by many fewer loading repetitions within each loading bout. Here, we examined the complementary hypothesis that the number of bouts per week of rest-inserted loading could be reduced from three bouts per week without loss of osteogenic efficacy. We conducted a series of 3-wk in vivo experiments that noninvasively exposed the right tibiae of mice to either cyclic (1 Hz) or rest-inserted loading interventions and quantified osteoblast function via dynamic histomorphometry. Although reducing loading bouts from three bouts per week (i.e., nine total bouts) to one bout per week (i.e., three total bouts) effectively mitigated the osteogenic benefit of cyclic loading, the same reduction did not significantly reduce periosteal bone formation parameters induced by rest-inserted loading. The osteogenic response was robust to the timing of the rest-inserted loading bouts (three bouts in the first week vs one bout per week for 3 wk). However, elimination of any single bout of the three one-bout-per-week bouts mitigated the osteogenic response to rest-inserted loading. Finally, periosteal osteoblast function assessed after the 3-wk intervention was not sensitive to the timing or number of rest-inserted loading bouts. We conclude that rest-inserted loading holds potential to retain the osteogenic benefits of mechanical loading with significantly reduced frequency of bouts of activity while also enabling greater flexibility in the timing of the activity.

Reply to Scott, Sale, Greeves, and Fraser

to the editor: We thank Scott et al.([1][1]) for their interest in our recent study ([2][2]) that examined the acute response of bone turnover markers to a single bout of resistance training (RT) or plyometrics (PLY). We appreciate the acknowledgement of the strengths of our study design: we

Measurement of osteogenic exercise – how to interpret accelerometric data?

Bone tissue adapts to its mechanical loading environment. We review here the accelerometric measurements with special emphasis on osteogenic exercise. The accelerometric method offers a unique opportunity to assess the intensity of mechanical loadings. We present methods to interpret accelerometric data, reducing it to the daily distributions of magnitude, slope, area, and energy of signal. These features represent the intensity level of physical activities, and were associated with the changes in bone density, bone geometry, physical performance, and metabolism in healthy premenopausal women. Bone adaptations presented a dose- and intensity dependent relationship with impact loading. Changes in hip were threshold dependent, indicating the importance of high-impacts exceeding acceleration of 4 g or slope of 100 g/s as an osteogenic stimulus. The number of impacts needed was 60/day. We also present the daily impact score to describe the osteogenic potential of daily mechanical loading with a single score. The methodology presented here can be used to study musculoskeletal adaptation to exercise in other target groups as well.

Mechanical Loading Down-Regulates Peroxisome Proliferator-Activated Receptor γ in Bone Marrow Stromal Cells and Favors Osteoblastogenesis at the Expense of Adipogenesis

Because a lack of mechanical information favors the development of adipocytes at the expense of osteoblasts, we hypothesized that the peroxisome proliferator-activated receptor gamma (PPARgamma)-dependent balance between osteoblasts and adipocytes is affected by mechanical stimuli. We tested the robustness of this hypothesis in in vivo rodent osteogenic exercise, in vitro cyclic loading of cancellous haversian bone samples, and cyclic stretching of primary stromal and C3H10T1/2 cells. We found that running rats exhibit a decreased marrow fat volume associated with an increased bone formation, presumably through recruitment of osteoprogenitors. In the tissue culture model and primary stromal cells, cyclic loading induced higher Runx2 and lower PPARgamma2 protein levels. Given the proadipocytic and antiosteoblastic activities of PPARgamma, we studied the effects of cyclic stretching in C3H10T1/2 cells, treated either with the PPARgamma activator, Rosiglitazone, or with GW9662, a potent antagonist of PPARgamma. We found, through both cytochemistry and analysis of lineage marker expression, that under Roziglitazone cyclic stretch partially overcomes the induction of adipogenesis and is still able to favor osteoblast differentiation. Conversely, cyclic stretch has additive effects with GW9662 in inducing osteoblastogenesis. In conclusion, we provide evidence that mechanical stimuli are potential PPARgamma modulators counteracting adipocyte differentiation and inhibition of osteoblastogenesis.

A School Curriculum–Based Exercise Program Increases Bone Mineral Accrual and Bone Size in Prepubertal Girls: Two-Year Data From the Pediatric Osteoporosis Prevention (POP) Study

This 2-year prospective controlled exercise intervention trial in 99 girls at Tanner stage 1, evaluating a school curriculum-based training program on a population-based level, showed that the annual gain in BMC, aBMD, and bone size was greater in the intervention group than in the controls. Most exercise intervention studies in children, evaluating the accrual of BMD, include volunteers and use specifically designed osteogenic exercise programs. The aim of this study was to evaluate a 2-year general school-based exercise intervention program in a population-based cohort of girls at Tanner stage 1. Forty-nine girls 7-9 years of age in grades 1 and 2 in one school were included in a school curriculum-based exercise intervention program of general physical activity for 40 minutes per school day (200 minutes/week). Fifty healthy age-matched girls in three neighboring schools, assigned to the general Swedish school curriculum of physical activity (60 minutes/week), served as controls. All girls were premenarchal, remaining in Tanner stage 1 during the study. BMC (g) and areal BMD (aBMD; g/cm2) were measured with DXA of the total body (TB), the lumbar spine (L2-L4 vertebrae), the third lumbar vertebra (L3), the femoral neck (FN), and the leg. Volumetric BMD (vBMD; g/cm3) and bone size were calculated at L3 and FN. Total lean body mass and total fat mass were estimated from the total body scan. Height and weight were also registered. Baseline measurements were performed before the intervention was initiated. Follow-up was done after 2 years. No differences between the groups were found at baseline in age, anthropometrics, or bone parameters. The annual gain in BMC was greater in the intervention group than in the controls: L2-L4, mean 3.8 percentage points (p = 0.007); L3 vertebra, mean 7.2 percentage points (p < 0.001); legs, mean 3.0 percentage points (p = 0.07). The intervention group had a greater annual gain in aBMD: total body, mean 0.6 percentage points (p = 0.006), L2-L4, mean 1.2 percentage points (p = 0.02), L3 vertebra, mean 1.6 percentage points (p = 0.006); legs, mean 1.2 percentage points (p = 0.007). There was also a greater mean annual gain in bone size in the L3 vertebra (mean 1.8 percentage points; p < 0.001) and in the FN (mean 0.3 percentage points; p = 0.02). A general school-based exercise program for 2 years for 7- to 9-year-old girls (baseline) enhances the accrual of BMC and BMD and increases bone size.

Calcium and Exercise Affect the Growing Skeleton

Adequate dietary calcium and bone-stimulating exercise during growth are known to affect skeletal development, but the combined effects of dietary calcium and osteogenic exercise have received scant attention. Animal research has showed a compensatory effect of impact loading on calcium-deprived bones, while various human studies have suggested compensatory, additive, or possibly synergistic effects in certain skeletal locations. Current evidence suggests that the best strategy for strong bones by the end of childhood may be either high-impact exercise with a moderate or greater calcium intake or a combination of moderate-impact exercise and adequate calcium during growth.